iPod nano/mini 2G use clock speed optimisation to increase battery time.VBR songs with a sudden increase in bitrate may cause the iPod nano/mini 2G to stutter as the clock speed is not increased fast enough to deal with the increased bitrate.

This has so far been observed for songs encoded with LAME --preset standard and is only true when not using the equaliser.

For Five Years the clock speed hovers around 24 jumping to 30 when the stuttering begins. Using the equaliser the clock speed hovers around 36 throughout the song and no stuttering occurs.

Further observations:- this problem is related to the iPod nano/mini 2G but one sample has been found that makes the 4G Color iPod stutter- problem with iPod mini software 1.3, 1.4, and 1.4.1- problem with iPod nano software 1.0, and 1.1- iPod mini 2G do not use optimisation when connected to a computer- iPod mini 2G do use optimisation, both when using its battery and when connected to a powered dock that is not connected to a computer- problem go away when using an EQ setting different from flat/off- only safe EQ setting to use is Bass Reducer / Treble Reducer in order to avoid distortion of songs with a high recording level- problem do not occur when using iTunes MP3 encoder- problem do not occur when LAME VBR song do not contain 320 kbps: options --preset standard -B 256- problem do not always occur at the same spot in the subtle songs listed below- iPod mini 1G clock speed for Five Years hoovers aroung 31 rising to 33 where it was 24 / 30 for the 2G- iPod mini optimisation may be turned off (I don't now how to provoke this) and require a reset of the iPod to turn it back on.- for the 4G color iPod only the sample with NIN - Right Where it Belongs stutters, even with the EQ set to Bass Reducer. Acoustic EQ setting makes the problem go away.